Liquid-heater.



UNITED STATES PATENT OFFICE.

HENRY BANDLOW, OF CHICAGO, ILLINOIS.

'LIQUID-HEATER.

Application filed October Toall whom 'it may concern.'

Be it known that I, HENRY E. BANQLOW, a citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Liquid-Heaters; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings, and to the characters of reference marked thereon, which form a part of this specification.

` This invention relates to improvements in quick or instantaneous liquid heaters and refers more particularly to that type of heaters which embrace a liquid heating vessel with means to heat the same, and a super-` posed reservoir to supply liquid to the heating vessel in such manner/as to avoid circulation of heated liquid back to the reservoir when liquid is being withdrawn from the heating vessel while permitting steam to be vented from said vessel to the reservoir.

The object of the invention is to improve and simpliiythe arrangement of the liquid circulating devices for the purpose set forth and the invention consists in the matters hereinafter set forth and more'particularly pointed out in the appended claims.

In the drawings,-Figure 1 is an axial vertical sectionoie a heater'embodying my invention. Fig. 2 is an enlarged axial section of the plug 33 shown in Fig. 1. Fig. 3 is a section similar to Fig. 2 showing a modification.

The casing of the heater comprises the sheet metal base 5 and the tubular upright portion G. Within said casing is supported a vertical heating vessel 8, said. heating vessel for the liquid comprising a sheet metal tube closed at its bottom and extending upwardly into the lower end of a tubular extension of the cast metal top piece 10, which constitutes in part a portion of the top wall of the casing and in part the top wall of the heating chamber vessel. The said cast metal top piece 10 constitutes the support for a liquid reservoir 11 usually made of glass which is located above the heating vesesl and is provided at its top with a removable cap piece 12 which normally closes the illing opening'of the reservoir.

The upper margin of the upright casing member 6 its within an annular slot formed in a thickened part or enlargement 14.- on the lbottom of the castinglO and said upright v tween the edges Specification of Letters Patent. Patente-(1 Jan. 10, v1911.

3, 1910. Serial. N0. 584,968.

member of the casing is clamped between the base and said cast top piece, and the base is attached to the latter through the medium of the rods 15 in the manner shown in Fig. 1. The reservoir is likewise held in place on the casting 10 by means of rods 18 which extend between and are attached at their ends to the casting 10 and to a clamping ring 21 fitted to the u per open side of the reservoir. Thev seat or the cap 12 is formed in said clamping ring 21. Compressible washers 22, 23 are interposed beof saidreservoir and said clamping ring and the tively, to protect said edges from breakage.

The tubular heating vessel 8 is surrounded by an electrical heating coil 25 which may be connected in any preferred manner with ,a supply circuit and with a switch.

The said coil is preferably wound about athin insulating layer 26 of mica or the like, which immediately surrounds the heating vessel. The coil is preferably in turn inclosed by a heat insulating sheath 27, of asbestos or the like, from the heat of the heating coil.

The liquid passes from the reservoir to the bottom of the heating vessel through a pipe 29 which extends at its upper end through an opening in the casting 10 (which constitutes the bottom wall of the reservoir and the top Wall ot' the heating vessel) and extends at its lower end to the bottom of said vessel. Liquid is drawn oii from the lupper end of the heating vessel 8 through a draw-oit pine 30 provided with a faucet 31, the inner end of said draw-oit pipe engaging a screw-threaded opening in a thickened portion of the tubular extension 9 of the top casting 10.

The present invention, constituting a part of the heater described,I relates toan improved means for controlling the circulation of the liquid being heated in such manner as to quickly heat the liquid `within ing vessel or tube 8 and avoidin the necessity of heating the entire body o liquid contained in the reservoir, time providing means for the escape of vapor or steamttrom the top of the heating vessel to the reservoir in the event that the liquid is raised to the vaporizing or steam temperature. l

In order to provide for suchcirculation as will heat the li uid inthe heating vessel without correspon ingly heating the liquid casting 10, .respec- I the heatwhile at the same to protect the casing the apertures, but will in the reservoir, and at the same time p rovide a vent for steam from the heating chamber to the reservoir, I have provided the top wall l0 of the heating vessel with an opening -in which is fitted a hollow plug 33, said plug being in open communication at its lower end with the heating vessel and closed at its upper end by the end wall 34. rlhe said hollow plug communicates with the reservoir through the medium of a plu-.

rality of small, constantly open, apertures 35 arranged in the vertical wall of the plug and disposed circularly about said wall. In order that steam escaping or venting through said apertures shall not be given a direct upward direction in a manner t0 escape d1- iectly upwardly through the body of liquid in the reservoir, I may provide the hollow plug abovesaid vent apertures with an annular flange 36 which overhangs said apertures so as to give the steam, when first issuing from t-he apertures, a lateral direction through the fluid. Said apertures 35 will preferably be given a slightly downward and outward inclination.

In Fig. 3 I have shown a form oihollow plug 38 in which the flange of the first described plug is omitted, and the vent apertures 39 thereof are inclined sharply downwardly and outwardly so as to give the steam which is vented therethrough a sharp downward inclination such as will prevent the di rect rise of the steam through the liquid in the reservoir as soon as it escapes through cause the steam to first-tend downwardly and more slowly upwardly when its velocity is reduced. By thus giving the steam a lateral or downward tendency as it issues from the apertured plug, there is less tendency of disturbing the liquid above the plug.

In operation, when it is desired to draw heated liquid. from the heater the current is switched into the heating coil and the heat generated in the coil acts to quickly heat the liquid in the vessel 8. lVhen the liquid has been raised to the proper temperature, i'equiring but a few seconds, the faucet 3l is opened to allow the liquid to flow from the heating vessel under the head of the column of liquid in the reservoir; the liquid passing from the reservoir through the tube 29 into the heating vessel to replace the liquid drawn from said vessel. The total area of the vent apertures 35 is so related to the area of the discharge or draw-off pipe 30 that, when the draw-ofi'l pipe is open, the heated liquid will .pass out of the heating vessel through the open draw-off pipe and no substantial volume of liquid will rise upwardly into the reservoir. In other words the vent apertures 35, while providing for escape or vent of steam from the heatinovessel to the reservoir at times when the l rawoff pipe is closed, constricts the How of liquid so that little or no liquid passes to the reservoir when the draw-off pipe is open. The liquid that passes from the reservoir to the lower end of the heating vessel, at a time when the draw-ofl` pipe is open, is heated by the time it reaches the draw-off pipe. Thus it will be seen that the body of liquid in the reservoir constitutes a supply for the heating vessel, and that when the draw-off pipe is opened to draw heated liquid from the heater, the heat of the coil or other heating device is applied only to that part of the liquid in the heating vessel, the constantly open restricted apertures preventing the heated liquid rising in substantial quantities into the reservoir. 'Ihe heat applied to the liquid is not, therefore, unnecessarily expended in the body of liquid in the reservoir, such as would occur if there were a free unrestricted flow of liquid from the heating vessel to the reservoir. If however the temperature of the liquid in the heating vessel shall rise to the steam oint at a time when the draw-off pipe is c osed, the steam willk be vented through the small apertures 35' and thereby avoid dangerous pressure in the heating vessel. Moreover sai vent apertures 35 avoid such pressure in the top of the heating vessel as will tend to depress the liquid level in said vessel below the draw-of` pipe, so that as soon as the draw-oft pipe is opened heated liquid begins at once to flow therethrough, without a preliminary discharge of steam` or vapor from the draw-off pipe.

The said hollow plug 33 or 3S ma be fixed in the opening in the top wall o the heating vessel in any suitable manner. As herein shown said top wall is provided with `a screw-threaded boss ll() and the plug is 105 screw-threaded to enter the same. The removability of the plug provides means whereby the heating vessel may be readily cleaned, inasmuch as free access may be had to said vessel when the reservoir and the hol- 110 low plug have been removed from place.

It will be manifest that the structural details of the heater may be somewhat varied from that herein shown and it will also be that heat may be cifically claimed.

claim as my invention l. A liquid heater comprising a heating vessel having means for heatin the same and provided at its upper end with a drawoif device, a reservoir ovei said heating vessel, and means for directingliquid from the reservoir to the bottom of said vessel, there being a constantly open passage between the upper end of the heater and the reservoir of such area relatively to the draw-off pipe as to prevent substantial circulation of heated water from the heating vessel to the reservoir when liquid is being drawn off through said pipe, while permitting the escape of the steam therethrough from the receptacle to the reservoir.

2. A liquid heater comprising a heating vessel having means for heating the same and provided at its upper end with a drawoil:1 pipe, a reservoir over said heating vessel, means for directing liquid from the reservoir to the lower end of the heating vessel, and a tubular member in open communication with the heating vessel and closed at its top and provided in its side walls with a plurality ot' small, constantly open vent openings atlording passage for steam therethrough from the heating vessel to the reservoir, while preventing the passage of a substantial volume of heated liquid from said vessel to the reservoir when the drawoti' pipe is open.

3. A liquid heater comprising a heating vessel having means for heating the same and provided at its upper end with a drawott' pipe, a reservoir over said heating vessel, means tor directing liquid from the reservoir to the lower end of the heating vessel, and a tubular member in open communication with the heating vessel and closed at its top and provided with a circular series of small, constantly open vent openings at'- ording passage for steam therethrough from the heating vessel to the reservoir, while preventing substantial escape ot heated liquid trom said vessel to the reservoir, with means to direct the steam laterallyr from said openings to prevent it rising directly7 from said openings upwardly through the reservoir.

a. A liquid heater comprising a heating vessel having means for heating the same and provided at its upper end with a drawott' pipe, a reservoir over said heating vessel,

means for directing liquid romthe reservoir to the lower end ot' the heating vessel, and a tubular member in open communication with the heating vessel and provided with a plurality ot downwardly inclined small vent openings affording passage for steam therethrough from the heating vessel to the reservoir, while preventing the escape ot heated liquid from said vessel to the reservoir when the draw-oit pipe is open.

5. A liquid heater comprising a heating vessel having means for heating the same and provided at its upper end with a drawoti pipe, a reservoir over said heating vessel, means for directing liquid from the reservoir to the lower end of the heating vessel, and a vertical tubular member in open communication with the heating vessel and closed at its top and provided below its top with a circular series of small openings, there being a flange at the top of said member which overhangs said openings, for the purpose set forth.

6. A liquid heater comprising a heating vessel having an electrical heating coil surrounding t-he same, a reservoir over said heating vessel, means for directing liquid from the reservoir to the lower side of the heating vessel, and a draw-off device at the upper end of the vessel, there being a plurality of small, constantly open vent openings alording passage for steam from the heating vessel to the reservoir, but preventing the flow of heated liquid in substantial quantities from said vessel to said reservoir when the draw-off device is open.

7 A liquid heater comprising a heating vessel having means for heating the same, a reservoir above said vessel, means for directing liquid from the reservoir to the bottom of said vessel, a draw-ott device at the top of the vessel, and a hollow plug removably fitted in the top wall of said vessel in open communication with said vessel and closed at its top, the wall of said plug being provided with a plurality of small openings affording passage of steam from said vessel to the reservoir but preventing passage of heated liquid in substantial quantities from said vessel to the reservoir when the drawotf device is open.

In testimony, that Iy claim the foregoing as my invention I aliiX my signature 1n the presence of two witnesses, this 1stdav ot October A. D. 1910.

HENRY E. BANDLOV. Witnesses:

W. L. HALL, WILLIAM GOLDBERGER. 

